In prior embodiments of such devices, it is necessary to interpose a whole series of accessories between the boiler as delivered from the factory and the external pipework therefor, particularly to make it possible to feed circuits with water under pressure (generally coming from an outside water main), and to provide respective stopcocks for each of these circuits, together safety precautions concerning excess pressure or leaks.
In addition, with such embodiments, it is not generally possible to apply pressure to the central heating circuit comprising the radiators for the purpose of leak testing until the boiler is installed: this constitutes a drawback while the premises to be fitted is still being built and is therefore not protected against theft or damage.
The invention enables these drawbacks to be remedied, and to this end it proposes that the connection portions for boilers of the type in question should be constituted by special "strips" which are particularly simple and cheap to make, which strips make it possible to test the central heating circuit under pressure in the absence of the boiler per se, i.e. in the absence of the active portion of the boiler comprising its burner and its heat exchangers.